java - modifying the vertical gabs between two elements in JList

Question

this is a part of my code :

    listNumber1 = new JList();
    listNumber1.setListData(numbers);
    listNumber1.setVisibleRowCount(5);
    scroll1 = new JScrollPane(listNumber1);
    scroll1.setPreferredSize(new Dimension(50,100));


    listOperations = new JList();
    listOperations.setListData(operations);
    listOperations.setVisibleRowCount(5);
    scroll2 = new JScrollPane(listOperations);
    scroll2.setPreferredSize(new Dimension(50,100));

    listNumber2 = new JList();
    listNumber2.setListData(numbers);
    listNumber2.setVisibleRowCount(5);
    scroll3 = new JScrollPane(listNumber2);
    scroll3.setPreferredSize(new Dimension(50,100));

My Question : How to increase the vertical gabs between (+), (-) and (*) to be like the middle JList in the picture

Answer 1

您可以尝试覆盖getFixedCellHeight()以返回 JList / 3 的高度。

Answer 2

您可以只使用空字符串作为间隙。这并不理想，因为如果用户选择它们，您将无需执行任何操作或显示用户友好的错误，但它会起作用。

Answer 3

根据 camickr 的回答：

要增加单元格高度：

 list.setFixedCellHeight(Hight );

对于问题高度 = 30将给出一个很好的结果：

 listOperations.setFixedCellHeight(30);